the Caro Kann defense.
The Caro-Kann Defence is a common chess opening characterized by the moves:1.e4 c6.The usual continuation is2.d4 d5followed by 3.Nc3 (the Classical Variation), 3.Nd2 (the Classical Variation), 3.exd5 (the Exchange Variation), or 3.e5 (the Advance Variation). 2.Nc3 is the modern variation which has gained much popularity. The Caro-Kann, like the Sicilian Defence and French Defence, is classified as a "Semi-Open Game", but it is thought to be more solid and less dynamic than either of those openings. It often leads to good endgames for Black, who has the better pawn structure.The opening is named after the English player Horatio Caro and the Austrian Marcus Kann who analyzed the opening in 1886. It is believed to be good against computers especially when it leads to a closed position. It is, hence, one of the more common openings played in computer-human matches.Classical / Capablanca VariationThe most common way of handling the Caro-Kann, the Classical Variation (often referred to as the Capablanca Variation after José Capablanca), is defined by the moves :
1.e4 c62.d4 d53.Nc3 (or 3.Nd2) dxe44.Nxe4 Bf5This was long considered to represent best play for both sides in the Caro-Kann. White usually continues5.Ng3 Bg66.h4 h67.Nf3 Nd78.h5 Bh79.Bd3 Bxd310.Qxd3
Although White's pawn on h5 looks ready to attack, it can prove to be a real weakness in an endgame.[1]Much of the Caro-Kann's reputation as a solid defence stems from this variation being so hard to crack. Black makes very few compromises in his pawn structure, and plays a timely c5 to contest the d4 square. Black has the options of castling queenside, castling kingside, and even leaving his king in the center. Should things proceed to an endgame, Black often stands well thanks to his solid pawn structure and kingside pawn majority.Smyslov / Karpov VariationAnother solid positional line, this variation is characterized by the moves1.e4 c62.d4 d53.Nc3 (or 3.Nd2) dxe44.Nxe4 Nd7
At one time named after the first world champion Wilhelm Steinitz, nowadays the variation is more often referred to as the Smyslov Variation after the seventh world champion Vasily Smyslov who played a number of notable games with it, or the Karpov Variation, after the twelfth World Champion Anatoly Karpov, in whose repertoire it appeared quite often. The short-term goal of 4...Nd7 is to ease development by the early exchange of a pair of Knights without compromising the structural integrity of his position. Play is similar to the Classical Variation except that Black has more freedom by delaying the development of his bishop, and is not forced to play it to the g6 square. However, this freedom comes at a cost as White enjoys added freedom in taking up space in the center, and often plays the aggressive 5.Ng5!? where Black's development is brought into question as well as the positional weakness of the f7-square. The famous last game of the Deep Blue-Garry Kasparov rematch where Kasparov committed a known blunder and lost was played in this very line.The Bronstein-Larsen Variation and Korchnoi Variation both begin with the following moves:
1.e4 c62.d4 d53.Nc3 dxe44.Nxe4 Nf6!?5.Nxf6The Bronstein-Larsen Variation arises after:5...gxf6!?Black has voluntarily opted for an inferior kingside pawn structure and a practical necessity of castling queenside, but also has some compensation in the form of the open g-file for the rook and unusually active play for the Caro-Kann. It is generally considered somewhat unsound, but former top-10 player Bent Larsen employed it with some success during the 1970s.The Korchnoi Variation arises after:5...exf6Viktor Korchnoi has played 5...exf6 many times (including in a world championship match). 5...exf6 is sounder than 5...gxf6!? of the Bronstein-Larsen Variation and offers Black rapid development.Advance variation: 3...Bf5 and 3...c5The 3...Bf5 variation that follows with1e4 c62d4 d53.e5 Bf5has gained popularity after having previously been widely regarded as inferior for many years, owing chiefly to the strategic demolition that Aron Nimzowitsch (playing as White) suffered at the hands of José Capablanca in one of their games at the New York 1927 tournament:
1.e4 c6 2.d4 d5 3.e5 Bf5 4.Bd3?! (after the exchange of the light-squared Bishops, Black's play is based on White's light-squared weakness) 4...Bxd3 5.Qxd3 e6 6.Nc3 Qb6 7.Nge2 c5?! (7...Ne7 8.0-0 Qa6) 8.dxc5 Bxc5 9.0–0 Ne7 10.Na4? (10.b4! Bxb4 (10...Qxb4 11.Nb5 Qa5 12.Be3 a6 13.Rab1 axb5 14.Bxc5 Nbc6 15.Rxb5 Qc7 16.Bd6 Qd7 17.Rfb1 Nd8 18.Rc5±) 11.Rb1 Qa5 12.Nb5= Moutousis-Cilia Vincenti, Thessalonika, 13.Nov.1988, 1–0) 10...Qc6 11.Nxc5 (11.Qg3 Nf5 12.Qb3 Nc6) 11...Qxc5 12.Be3 Qc7 13.f4 Nf5 14.c3 Nc6 15.Rad1 g6 16.g4 Nxe3 17.Qxe3 h5 18.g5 0–0 19.Nd4 Qb6 20.Rf2 Rfc8 21.a3 Rc7 22.Rd3 Na5 23.Re2 Re8 24.Kg2 Nc6 25.Red2 Rec8 26.Re2 Ne7 27.Red2 Rc4 28.Qh3 Kg7 29.Rf2 a5 30.Re2 Nf5 31.Nxf5+ gxf5 32.Qf3 Kg6 33.Red2 Re4 34.Rd4 Rc4 35.Qf2 Qb5 36.Kg3 Rcxd4 37.cxd4 Qc4 38.Kg2 b5 39.Kg1 b4 40.axb4 axb4 41.Kg2 Qc1 42.Kg3 Qh1 43.Rd3 Re1 44.Rf3 Rd1 45.b3 Rc1 46.Re3 Rf1 0–1.The Advance Variation has since been revitalized by aggressive lines such as the Bayonet Attack (4.Nc3 e6 5.g4) favored by Latvian Grandmaster Alexei Shirov or the less ambitious variation (4.Nf3 e6 5.Be2 c5 6.Be3) popularized by English Grandmaster Nigel Short.The 3...c5 variation that follows with1.e4 c62.d4 d53.e5 c5!?is an important alternative and avoids the weight of theory associated with 3...Bf5. It was used by Mikhail Botvinnik in his 1961 match vs. Mikhail Tal (though with a negative outcome for Botvinnik – 2 draws and a loss).The line was christened the "Arkell/Khenkin Variation" in the leading chess magazine "New in Chess" yearbook 42 in recognition of the work these two Grandmasters did and the success they were having with the variation. In comparison to the French defense, Black lacks the tempo normally spent on ...e6. However, White can only exploit this by the weakening of his own central bind with 4. dxc5 when Black has good chances of regaining the pawn.Exchange variation and Panov-Botvinnik AttackThe Exchange Variation is 1.e4 c6 2.d4 d5 3.exd5 cxd5.The Panov-Botvinnik Attack begins with the move 4.c4. It is named after Vasily Panov and the world champion Mikhail Botvinnik. This system often leads to typical isolated queen's pawn (IQP) positions, with White obtaining rapid development, a grip on e5, and kingside attacking chances to compensate for the long-term structural weakness of the isolated d4 pawn. The major variation in this line 4...Nf6 5.Nc3 e6 6.Nf3, when Black's main alternatives are 6...Bb4 (a position characteristic of the Nimzo-Indian Defense) and 6...Be7 (the most popular). 6...Nc6?! is inferior as it is favorably met by 7.c5!, after which White plans on seizing the e5-square via the advance of his b-pawn to b5 or by exchanging the Black's Knight on c6 after Bb5.The "true" Exchange Variation begins with 4.Bd3 Nc6 5.c3 Nf6 6.Bf4 Bg4 7.Qb3. White isn't thought to possess much of an advantage, although the line was tried by Bobby Fischer. Play is somewhat similar to the Queen's Gambit Exchange Variation (1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.cxd5 exd5), colors reversed.